Well RES,as well as many other reptiles/amphibians, are believed carriers of Salmonella and some other nasty little germs. It's true there is a risk, but it can be greatly reduced to a bare minimum if you take care of yourself, and Clover.
Steps for yourself and roomates would be;
1)Wash hands thoroughly(not with abrasive cleaners/soaps,cause it can irritate the RES) before handling.
2)Make sure that your RES doesn't have any weird looking fungus or bacteria on its body, before putting it anywhere in your home/room.(If unsure of the bacteria or unable to clean it, take Clover to the vet and checked out).
3)Your friends can't overly crowd Clover or "make" her do stuff, like walk a certain way. Because this can stress Clover out and cause sickness in Clover and potentially the rest of you.
4) If you make a pen, make sure their's no sharp or un-even surfaces that can catch Clover's skin or even trap/ensnare her, making her panic,which in turn causes stress.
5) Important: don't leave Clover in places where she can get stuck or flip over, especially since if it's out of eye-shot, cause that wouldn't turn out well for her

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I personally, reccomend an outside enclosure(not permanent, just to play and stuff), because its more natural and plus she would get direct sunlight. My family didn't want a turtle in the house,period(though I've managed to persuade them to let her come in). So I made a deal(that's still stands), that they have the front yard and I get the backyard. I built fences and a wall to prevent escape, as well as to keep out pesky predators/animals.(Animals are free to roam here)
So if you don't have a back/front yard and still want a house-roaming RES, I suggest getting splinter-free wood/fence, setting it up somewhere close to sunlight(with shade),but not where everyone has to come into contact with stuff(kitchen for example) and maybe some soft carpet or fabric for Clover to grip as she walks.
I hope your situation works out well! (Sorry for the long answer

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